<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>hover示例</title>
		<style type="text/css">
			body {
				background: url(img/bg.jpg);
				min-height: 500px;
				margin: 0;
				padding: 0;
			}

			.top {
				width: 100%;
				height: 80px;
				background: url(img/wrapAbg.png) top left repeat-x;
			}

			.listdiv_border {
				width: 100%;
				height: 500px;
				display: flex;
				justify-content: space-around;
			}

			.listdiv_border div {
				width: 30%;
				height: 100px;
				overflow: hidden;
				margin-top: 50px;
			}

			.listdiv_border div:hover {
				height: 200px;
				transition: all 0.5s;
				border-radius: 5px;
				box-shadow: 0px 0px 5px #999999;
			}

			.info-tab {
				position: relative;
			}

			.info-tab::after {
				content: '';
				border: 8px solid transparent;
				border-top-color: #2c8ac2;
				position: absolute;
				top: 3px;
			}
		</style>
	</head>
	<body>
		<div class="top"></div>
		<div class="listdiv_border">
			<div style="background: #0000FF;">
				<div class="text_center" style="width: 100%;margin-top: 100px;">aaaaaaaaaaaaaaaaaa</div>
			</div>
			<div style="background: #008000;"></div>
			<div style="background: #999999;"></div>
		</div>
		<div class="info-tab">123</div>
		<div class="info-tab">123</div>
		<div class="info-tab">123</div>
		<div class="info-tab">123</div>
	</body>
</html>
